When you want an egg dish to feed a crowd or make enough breakfast for the week, breakfast casseroles are just the ticket. Eggs hold together whatever ingredients you want to put in the baking dish, and in this case it’s a filling combination of frozen diced potatoes, savory sausage, a whole bag of baby spinach, and, of course, a few handfuls of shredded cheese. This casserole is a bit like a diner omelette and breakfast potatoes all in one dish, and it’s nice to start the day knowing you’ve already had a serving of greens!